Hoisting mechanism.



L. H. BRINKMAN.

v HOISTING MEOHANISM.

APPLICATION FILED oc'r. 29, 1904.

953, l 92. Patented Mar. 29, 1910.

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UNITED STATES T OFFICE.

LOUIS H. BRINKMAN, OF WEST HARTFORD, CONNECTICUT, ASSIGNOR TO WHITLOCKCOIL PIPE COMPANY, OF WEST HARTFORD, CONNECTICUT, A CORPORATION OFCONNECTICUT.

HOISTING MECHANISM.

Specification of Letters Patent.

Patented Mar. 29, 1910.

To all 'whom it may concern:

Be it known that I, LOUIS H. BRINKMAN, a citizen of the United States,residing at West Hartford, in the county of Hartford and State ofConnecticut, have invented a new and useful Improvement in HoistingMechanism of which the following is a specification, accompanied bydrawings forming a part of the same, in which- Figure 1 is a centralvertical section of a hoisting mechanism embodying my invention. Fig. 2is an end View on a reduced scale showing my method of applying auniform force to the winding drum, and Fig. 3 is a diagrammatic Viewillustrating the cam surfaces on the check wheel 19.

Similar reference letters and figures refer to similar parts in thedifferent views.

My invention relates to means for applying a uniform rotating force toportable and fixed hoists so that the winding drum may be rotatedwhenever the resistance of the load to be lifted is less than the forceapplied to it7 and consists in the following described arrangement ofparts.

The construction and operation of those parts of my hoisting mechanismby which the force applied is multiplied at the winding drum is wellknown and is similar to that in common use which may be describedbriefly as follows. Referring to the accompanying drawings 1 isa toothedwinding drum, or sheave, attached to a hollow main shaft 2 and which hasits periphery formed to engage with the links of a lifting chain 3, Fig.2, having a hook 4 at its lifting end. 5 is the driving sheave which iskeyed to the shaft 6 which latter turns within the shaft 2, and theshaft 2 carries the winding sheave l which runs in bearings in theframes 7 and 8. At the end of the shaft G is a pinion 9 which engagespinions 10, 10, rotating on studs 10a, 10a, held in a ring 11 and aHarige 12 on the hollow shaft 2. The pinions l0, l0, also engage withthefixed internal annular gear 13 forming part of the frame 8.

y The frame 8 is connected with the frame 7 by studs, one of which isshown at 14. The stud 14 forms the pivot of the yoke 15, by which theconnected frames 7 and 8 arel suspended. The yoke l5 is provided with aside horn 16 to which is attached one end of the brake strap 17 whichembraces the brake pulley 18, having a flange 19 inclosing the checkwheel 20 clutched to the driving sheave 5 by an arm 21. The periphery ofthe check wheel has a series of short cam surfaces 22, as shown in Fig.3, each provided with a friction roller 23, which allows the cheek wheelto turn in one direction, but prevents its opposite movement by thewedging action of the rollers 23.

The above described hoistin mechanism is substantially like that shownin the United States Letters Patent to Thomas A. Weston, No. 413,004,dated October 15, 1889, to which Letters latent reference is hereby madefor a more detailed description. In my improvement I place on theoutside of the driving sheave 5 a ratchet wheel 24 also keyed to theshaft (i, and I pivot on the shaft (i a lever 25 to which I pivot at 2Ga pawl 27 held in engagement with the teeth of the ratchet wheel 24 bythe spring 28. Adjustably fastened to the lever 25 is a weight 29, whichweight may be varied as desired both in size and position. To the end 30of the lever 25 is attached a chain 31, the other end of which isattached to an eccentric strap 32 on an eccentric 33 on a rotating shaft34. By the revolution of the shaft 34 and eccentric 33, the end 30 ofthe lever 25 may be raised, thereby raising the pawl 27 against thedownward strain exerted by the weight 29 and without movement of theratchet wheel 24. On the further revolution of the eccentric 33, thechain 31 is lowered, thereby slackening the chain between the eccentric33 and the lever 25, allowing the weight 29 to exert a force to rotatethe ratchet wheel 24 through the pawl 27. If the force applied to rotatethe ratchet wheel 24 is in excess of the resistance offered by the loadattached to the hook 4, the shaft will be turned and the hoistingmechanism will be put in action to raise the load. The lever 25 will becarried down by the weight 29 to the end of the slack chain 31 and willassume the position shown by the dotted lines 35 from whence it is againraised by the continued revolution of the eccentric 33 causing the pawl27 to engage another tooth on the ratchet wheel 24, and the operation isrepeated. If the load on the hook 4 exerts a greater resistance than theforce exerted by the weight 29 the ratchet wheel 24 will not be rotatedand the eccentric 33 will rotate without result. The force of the weight29, however, will be exerted on the ratchet wheel 24 uniformly, and themovement of 'ratchet wheel operatively connected with the ratchet wheelwill take place whenever.v

the force of the weight 29 exceeds the load on the hook 4. A chain 36 isapplied to the sheave so that the hoisting mechanism may be rotated byhand if desiredin order to quickly take up any slack in the liftingchain 3.

My improved hoisting mechanism is adapted for use whenever it is desiredto eX- ert a uniform lifting force on the chain 3, and the amount offorce exerted may be adjusted at will by varying the position of theweight 29 on the lever 25.

What I claim as my invention and desire to secure by Letters Patent isl. In a hoisting' mechanism, the combination with a winding drum orsheave, of a ratchet wheel operatively connected with said winding drum,a pivoted lever, a pawl onvsaid lever to engage said ratchet wheel,means for exerting a uniform downward strain on said lever, said meanslocated on the same side of the pivot of said lever as said pawl,whereby said ratchet wheel is rotated by said downward strain, and meansfor intermittently lifting said pawl against said downward strainwithout movement of said ratchet wheel.

2. In a hoisting mechanism, the combination with a winding drum orsheave, of a said winding drum, a lever pivoted concentrically with saidratchet wheel, a pawl on said ratchet lever to engage said ratchetwheel, means for exerting a uniform downward strain on said lever, saidmeans located on the same side of said pivot as said pawl, whereby saidratchet wheel is rotated by said downward strain, a rotating shaft andmeans actuated by said rotating shaft for lifting said lever againstsaid downward strain to provide for the engagement of another tooth ofsaid ratchet wheel by said pawl.

3. In a hoisting mechanism, the combination with a winding drum orsheave, of a pivoted lever arranged to revolve said winding drum by adownward movement of said lever, means for exerting a uniform downwardstrain on said lever to revolve said drum, and means for lifting saidlever at regular intervals against said downward strain without movementof said drum.

4. In a hoisting mechanism, the combination with a winding drum orsheave, of a ratchet wheel operatively connected with said winding drum,a pivoted lever, a pawl pivoted to said lever to engage said ratchetwheel, a weight adjustably attached to said lever, and a rotating shaftprovided with an eccentric having an eccentric strap connected with theend of said lever.

5. In a hoisting mechanism, the combination with a winding drum orsheave, of a ratchet wheel operatively connected with said winding drum,means for intermittently rotating said ratchet wheel, means actingautomatically for holding said ratchet Wheel from backward rotation,comprising friction rollers arranged to prevent the backward rotation ofsaid ratchet wheel.

Dated this th day of October 1904.

LOUIS II. BRINKMAN.

IVitnesses E. D. REDFIELD, F. B. SMITH.

